1. Field of the Invention
The present invention relates to a method of creating caption-based search information for a moving picture stream of a video title recorded on a disk storage medium and performing a search of the moving picture stream by using the caption-based search information in a video disk reproduction apparatus like a DVD player, and a reproduction apparatus using such a method.
2. Description of the Related Art
Video reproduction systems with a caption display function like a video cassette recorder (VCR) are, in most cases, used to offer an effective means for studying foreign languages. For caption data in a VCR, video signals including character signals for caption are recorded on a video tape, and while the tape is reproduced, the character signals are selectively added to an image signal in the video signal so that the caption can be displayed in a superposed relationship to an image.
Meanwhile, several information storage media such as digital versatile disk (DVD) and DVD-ROM have been recently released in the market for use as multimedia optical disks. For example, a DVD-ROM that has a diameter of 120 mm and a storage capacity of around 4.7 GB on one side is suited for storage of several video titles in which multiple sub-picture channels and multiple audio channels are provided.
In DVD, caption data is recorded in the sub-picture channels in the form of bit-mapped image signals. While DVD is reproduced, the sub-picture data is read out and is then added to an image signal so as to display the caption.
While viewing a video title in foreign language audio mode, it often happens that a viewer wants to see a particular caption again. At this time, it is necessary for the viewer to manually perform searching of the moving picture stream which is reproduced with the caption by using search commands offered by the DVD reproduction apparatus and to resume the reproduction operation. The search is generally made by manually operating backward/forward movement keys or reproduction time search operation. Accordingly, it often takes many steps of pause-and-movement operations to precisely locate the moving picture data which is linked to the caption that the viewer wants to see, resulting in slow search time and the viewer""s inconvenience.
It is a primary object of the present invention to provide a method of creating caption-based video search information, in which each caption information is linked to the location of its associated moving picture stream which is reproduced concurrently with the caption information, in a moving picture data storage medium like DVD.
It is another object of the present invention to provide a method of and apparatus for performing search of moving picture stream corresponding to caption data which is chosen by a viewer in a caption list display window with reference to the caption-based moving picture stream search information.
To achieve the object, the present invention provides a method of creating caption-based search information for moving picture data of a data storage medium, comprising the steps of: searching moving picture data recorded on the storage medium for data including caption information; obtaining the location of the moving picture data to be concurrently reproduced with the caption information discovered in said searching step; and storing link information including the caption information and the location of the corresponding moving picture data.
The method of performing a caption-based search for moving picture data of a data storage medium according to the present invention comprises the steps of: creating and storing link information including caption information and moving picture data to be reproduced concurrently with the caption information; displaying part of the stored caption information; searching the created link information for the location of moving picture data, which is correspondent to a particular caption information chosen by a viewer from a list of caption information displayed on a screen; and resuming reproduction of moving picture data of the storage medium from the location of moving picture data discovered by said searching step.
In the method and apparatus according to the present invention, all caption data are extracted while video titles recorded on a DVD are scanned, and they are stored together with location information of moving picture data, each of which is linked to its associated caption data in terms of reproduction time. When the DVD is reproduced, a list of parts of the caption data is displayed on a screen in which a viewer can choose a caption the viewer wishes to listen or see. Upon choosing of a particular caption, the location of moving picture data linked with the selected caption is obtained from the link information between caption data and moving picture data. The reproduction of the DVD is then resumed at the location of the moving picture data.